# US 11,028,484 B2 · Electroless nickel plating of silicone rubber > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,028,484 B2 - Document ID: US11028484B2 - Status: Granted - Kind: B2 - Application number: 16/345,684 - Filed: 2017-10-30 - Published: 2019-11-21 - Granted: 2021-06-08 - Earliest claimed: 2016-11-03 - Assignees: Agency for Science, Technology and Research - Applicants: Agency for Science, Technology and Research - Inventors: Shengqin Wang; Yew Wei Leong - Web page: https://patentgrep.com/patent/US11028484B2 ## CPC - C23C 18/32: Coating with nickel, cobalt or mixtures thereof with phosphorus or boron (C23C18/50 takes precedence) - C08K 3/013: Fillers, pigments or reinforcing additives - C08K 5/04: Oxygen-containing compounds {(C08K5/0091 takes precedence)} - C08K 5/05: Alcohols; Metal alcoholates - C08K 5/1565: Five-membered rings - C08K 5/17: Amines; Quaternary ammonium compounds - C08L 83/04: Polysiloxanes - C23C 18/1216: {Metal oxides (C23C18/1212 takes precedence)} - C23C 18/1653: {Two or more layers with at least one layer obtained by electroless plating and one layer obtained by electroplating} - C23C 18/1893: {with use of organic or inorganic compounds other than metals, first} - C23C 18/208: {with use of metal first} - C23C 18/285: {Sensitising or activating with tin based compound or composition} - C23C 18/30: Activating {or accelerating or sensitising with palladium or other noble metal} - H01B 1/22: the conductive material comprising metals or alloys - C08K 2003/2241: {Titanium dioxide} - C23C: COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL (making metal-coated products by extrusion B21C23/22; covering with metal by connecting pre-existing layers to articles, see the relevant places, e.g. B21D39/00, B23K; metallising of glass C03C; metallising mortars, concrete, artificial stone, ceramics or natural stone C04B41/00; enamelling of, or applying a vitreous layer to, metals C23D; treating metal surfaces or coating of metals by electrolysis or electrophoresis C25D; single-crystal film growth C30B; by metallising textiles D06M11/83; decorating textiles by locally metallising D06Q1/04) - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - H01B: CABLES; CONDUCTORS; INSULATORS; SELECTION OF MATERIALS FOR THEIR CONDUCTIVE, INSULATING OR DIELECTRIC PROPERTIES (selection for magnetic properties H01F1/00; waveguides H01P {; printed circuits H05K}) ## Abstract According to the present disclosure, a method for coating nickel on an organosiloxane polymer wherein the said method comprises the steps of; forming a transition metal oxide on the organosiloxane polymer; etching the transition metal oxide with a basic solution; contacting the organosiloxane polymer comprising the etched transition metal oxide with an aqueous solution comprising a positively charged species to attach the positively charged species on the etched transition metal oxide; depositing a metal catalyst on the positively charged species; and treating the metal catalyst with an acidic solution to develop an activated organosiloxane polymer before transferring the activated organosiloxane polymer to a solution comprising nickel and/or nickel derivatives. A nickel organosiloxane composite is provided herein comprising a transition metal oxide layer and a positively charged species attached on the said oxide layer with nickel coated in the said positively charged species. ## Claims ### Claim 1 A method for coating nickel on an organosiloxane polymer comprising: forming a transition metal oxide on the organosiloxane polymer; etching the transition metal oxide with a basic solution; contacting the organosiloxane polymer comprising the etched transition metal oxide with an aqueous solution comprising a positively charged species to attach the positively charged species on the etched transition metal oxide; depositing a metal catalyst on the positively charged species; and treating the metal catalyst with an acidic solution to develop an activated organosiloxane polymer before transferring the activated organosiloxane polymer to a solution comprising nickel and/or nickel derivatives. ### Claim 2 (depends on 1) The method according to claim 1, wherein the organosiloxane polymer is selected from the group consisting of polydimethylsiloxane, vinyl methyl polysiloxane, phenyl methyl polysiloxane, phenyl vinyl methyl polysiloxane, fluoro vinyl methyl polysiloxane, and derivatives of silicone rubber, wherein the polysiloxane comprises at least one quaternary silicon. ### Claim 3 (depends on 1) The method according to claim 1, wherein the transition metal oxide comprises titanium oxide. ### Claim 4 (depends on 1) The method according to claim 1, wherein the forming comprises contacting the organosiloxane polymer with a solution comprising a swelling agent and a transition metal oxide precursor for up to 30 minutes, and drying the organosiloxane polymer in ambient conditions comprising a temperature from 15° C. to 30° C. and a relative humidity from 30% to 70% to form the transition metal oxide on the organosiloxane polymer. ### Claim 5 (depends on 4) The method according to claim 4, wherein the swelling agent comprises isopropyl alcohol. ### Claim 6 (depends on 4) The method according to claim 4, wherein the transition metal oxide precursor comprises titanium isopropoxide. ### Claim 7 (depends on 4) The method according to claim 4, wherein the transition metal oxide precursor and the swelling agent comprise a volume ratio of 1:1 to 1:99. ### Claim 8 (depends on 1) The method according to claim 1, wherein the positively charged species attached on the etched transition metal oxide changes polarity of charges present on the etched transition metal oxide. ### Claim 9 (depends on 8) The method according to claim 8, wherein the positively charged species is selected from the group consisting of positively charged nanoparticles or nanocolloids, dendrimers comprising nitrogen, polymers having at least one primary amine, secondary amine, tertiary amine, pyridinyl, quaternized amine, quaternized pyridinyl, and their mixtures thereof. ### Claim 10 (depends on 1) The method according to claim 1, wherein the metal catalyst comprises tin-palladium (Sn—Pd) colloidal metal catalyst. ### Claim 11 (depends on 10) The method according to claim 10, wherein the tin-palladium colloidal metal catalyst is prepared by: dissolving PdCl2 in an amount of 0.05 gram to 0.15 gram in 30 ml to 50 ml of HCl to form a first solution; dissolving SnCl2 in 10 ml to 30 ml of HCl and subsequently adding 10 ml to 30 ml of water to form a second solution; mixing the first and second solutions, and continuously stirring the mixture for 10 minutes to 30 minutes; dissolving 4 gram to 5 gram of NaCl, 0.4 gram to 1.2 gram of NaSnO3 and 5 gram to 15 gram of SnCl2 in 40 ml to 60 ml of water to form a third solution; adding the third solution to the mixture over a duration of 20 minutes to 40 minutes; and incubating the mixture under continuous stirring for 3 hours to 5 hours at 60° C. to 70° C. ### Claim 12 (depends on 11) The method according to claim 11, wherein concentration of the HCl forming the first solution and the second solution is 4 to 8 M and 9 to 12 M, respectively. ### Claim 13 (depends on 1) The method according to claim 1, wherein the solution comprising nickel and/or nickel derivatives is prepared by mixing 4 to 6 g/l of NiSO4, 0.5 to 1.5 g/l of NaH2PO4, 0.5 to 1.5 g/l of oxycarboxylic acid, and an amount of ammonia sufficient to maintain pH of the ENP solution between 4.5 and 5.5. ### Claim 14 (depends on 1) The method according to claim 1, wherein the forming further comprises preparing the organosiloxane polymer, wherein the preparing comprises: blending an organosiloxane polymer precursor with a cross-linking agent to form a blended mixture and curing the blended mixture at 170° C. to 180° C. under 8 MPa to 12 MPa for at least 5 minutes; or mixing two organosiloxane polymer precursors with a curing agent and curing at 25° C. to 35° C. for 48 hours.